Physically unclonable function (PUF) and true random number generator (TRNG) are the indispensable primitives for the Internet-of-Things (IoT) security. In this article, a highly robust unified ...PUF<inline-formula> <tex-math notation="LaTeX">/ </tex-math></inline-formula>TRNG design is demonstrated. An entropy source (ES) chip based on 40-nm resistive random access memory (RRAM) is designed and fabricated, and a pseudo-forming technique is developed to ensure excellent robustness. The unified PUF<inline-formula> <tex-math notation="LaTeX">/ </tex-math></inline-formula>TRNG is tested across <inline-formula> <tex-math notation="LaTeX">- 55\,\,^{\circ }\text{C} </tex-math></inline-formula> to 125 °C with different supply voltages, achieving < 0.001% bit error rate (BER) and >0.999 worst case min-entropy simultaneously. Excellent randomness is verified by NIST SP800-22 and 90B tests. This highly robust unified design can implement an authentication system with the authentication error rate (AER) approaching 0% and thus is promising for future IoT security applications.
Physically unclonable function (PUF) has been increasingly used as a promising primitive for hardware security with a wide range of applications in the Internet of Things (IoT). In recent years, ...novel PUF techniques based on resistive switching mechanism in various emerging nonvolatile memories have demonstrated superior performance on reliability and integration density. In this work, a resistive random access memory (RRAM)-based PUF chip with 8-kb capacity is developed. Two operation modes, namely differential mode and median mode, are embedded on chip. To implement these modes, a current sampling-based sense amplifier is designed to distinguish the current values of the PUF cells and the reference cell. In addition, a split-resistance scheme is proposed to enhance the PUF's reliability significantly. The experiment results show that the differential PUF exhibits excellent performance with native bit error rate (N-BER) below 6 <inline-formula> <tex-math notation="LaTeX">\times </tex-math></inline-formula> 10 −6 and inter-Hamming distance (inter-HD) of 49.99%. In the meanwhile, the reconfigurability of PUF challenge-response pairs (CRPs) is demonstrated with 49.77% and 47.29% reconfigure-Hamming distance (reconfigure-HD) in the median mode and the differential mode, respectively.
Polarization control of dual‐wavelength high peak power Raman lasers based on passively Q‐switched technology and yttrium vanadate (YVO4) crystal are widely used for generating novel laser sources, ...terahertz wave, material processing, and manipulating microparticles. However, the Raman lasers are usually linear polarization. Here, elliptical polarizations with controllable ellipticity and azimuthal angle are manipulated by adjusting the crystalline orientation of a‐cut YVO4 crystal in a passively Q‐switched Raman laser constructed with a Cr4+,Nd3+:Y3Al5O12 (Cr,Nd:YAG) crystal and a a‐cut YVO4 crystal. The ellipticity of the elliptically polarized dual‐wavelength Raman laser varies in a sinusoid modulation as a‐cut YVO4 crystal rotates with respect to the major axis of the intracavity fundamental laser and increases with applied pump power. The azimuthal angle varies in the same speed as a‐cut YVO4 crystal rotates. Anisotropic behavior of sinusoidal modulation of output power, pulse energy, and peak power is observed as a‐cut YVO4 crystal rotates. There are four peaks and four troughs for ellipticity, output power, pulse energy, and peak power within a 360° rotation of a‐cut YVO4 crystal. This work provides a solid and simple method for developing elliptical polarization controllable dual‐wavelength passively Q‐switched Raman laser with high peak power for various potential applications.
By using a Cr4+,Nd3+:Y3Al5O12 (Cr,Nd:YAG) crystal as working medium, and a‐cut yttrium vanadate (YVO4) crystal as Raman gain medium and birefringent material, dual‐wavelength Raman laser with manipulated elliptical polarization is demonstrated in a Cr,Nd:YAG/YVO4 self‐Q‐switched Raman laser by rotating a‐cut YVO4 crystal. High beam quality and high peak power dual‐wavelength Raman lasers with controllable elliptical polarization are promising sources for practical applications.
Physically unclonable function (PUF) and true random number generator (TRNG) are critical primitives to provide lightweight hardware protection. As area is tightly restricted in IoT applications, ...merging PUF and TRNG is a novel trend to achieve higher area efficiency. In this work, a novel tri-functional module is proposed and experimental demonstrated using RRAM for the first time. A two-phase forming process is designed to generate and store PUF ID utilizing the impact of different forming conditions on the switching window. As PUF ID is stored by the switching window, instead of a fixed resistance, PUF cells can be written to low resistance state and high resistance state as usual, and can be used as memory and TRNG. The inter-Hamming distance of the generated PUF IDs approaches 0.5, and with the majority voting readout strategy, low BER can be achieved in a wide range of temperatures from −40°C to 125°C. TRNG produces the true random numbers based on the parity of the number of pulses consumed in a write-zero process. The generated random numbers are uniform and uncorrelated after XORed, and the statistical randomness is verified by NIST SP800-22 tests.
Federated learning (FL) requires frequent uploading and updating of model parameters, which is naturally vulnerable to gradient leakage attacks (GLAs) that reconstruct private training data through ...gradients. Although some works incorporate differential privacy (DP) into FL to mitigate such privacy issues, their performance is not satisfactory since they did not notice that GLA incurs heterogeneous risks of privacy leakage (RoPL) with respect to gradients from different communication rounds and clients. In this paper, we propose an Adaptive Privacy-Preserving Federated Learning (Adp-PPFL) framework to achieve satisfactory privacy protection against GLA, while ensuring good performance in terms of model accuracy and convergence speed. Specifically, a leakage risk-aware privacy decomposition mechanism is proposed to provide adaptive privacy protection to different communication rounds and clients by dynamically allocating the privacy budget according to the quantified RoPL. In particular, we exploratively design a round-level and a client-level RoPL quantification method to measure the possible risks of GLA breaking privacy from gradients in different communication rounds and clients respectively, which only employ the limited information in general FL settings. Furthermore, to improve the FL model training performance (i.e., convergence speed and global model accuracy), we propose an adaptive privacy-preserving local training mechanism that dynamically clips the gradients and decays the noises added to the clipped gradients during the local training process. Extensive experiments show that our framework outperforms the existing differentially private FL schemes on model accuracy, convergence, and attack resistance.
Pharmacogenetics may help physicians deliver individualized treatments based on how a person's genes affect a drug's effects and metabolism. This information can help prevent adverse events or ...improve drug efficacy by enabling the physician to optimize dosage or to avoid a medication with adverse reactions and to prescribe an alternative therapy. This article discusses the current clinical utility of pharmacogenetic testing in the context of a patient who requires anticoagulation with warfarin.
This study explores a selection of solo piano works by the well-known French composer, Claude Debussy, and two contemporary Chinese composers, Huang Ruo and Liang Lei. The selected works demonstrate ...inspiration and impressions from various types of artworks, namely Oriental paintings and lacquer, an ancient story from Zen Buddhism, and Chinese folk songs. The document consists of two parts. The first part contains a brief biography of Debussy, Impressionist stylistic features, and musical techniques employed in Images I and Images II that represent the essence and characteristics of Debussian music, along with a descriptive analysis of each piece in the two sets. The second part provides biographical information about Huang Ruo and Liang Lei and literature related to the art objects that inspired their works. This section also details musical approaches and ideas employed by the two composers that deliver their distinct aesthetics and unique personal messages through their individual musical languages.
•One-dimensional vortex-arrays with singularity tuned from 1 to 4 have been achieved.•Four-singularity vortex-array with peak power of 5.56 kW has been achieved.•A method for developing pulsed ...one-dimensional vortex-array with tunable singularity.
One-dimensional (1D) vortex-arrays with multiple-singularity aligning along a line are flexible for microparticle manipulation, high capacity storage, material processing. Moreover, a high peak power one-dimensional vortex-array with large singularity enables assemble processing. The development of a miniature laser to directly generate one-dimensional vortex-array with tunable singularity is of great value for practical applications. However, solid-state lasers for this purpose was limited by the low power, low efficiency and less singularity achieved. Here, we demonstrate a simple and robust method for directly generating one-dimensional vortex-array with singularity tunable upon to 4 in a tilted Nd:YAG/Cr4+:YAG composite crystal passively Q-switched (PQS) microchip laser, irradiated by a decentered annular beam (DAB). The singularity of one-dimensional vortex-array can be tuned from 1 to 4 by controlling the offset of collimating lens, Δx. The average output power of one-dimensional vortex-array with 4 singularities is 0.76 W at Pin = 5.66 W, the optical conversion efficiency is 13.4%. One-dimensional vortex-array with 4 singularities processes pulse width of 3.5 ns, peak power of 5.56 kW. The achieved results suggest the potential that DAB can be used a practical pump beam in PQS microchip laser for generating nanosecond, high peak power one-dimensional vortex-arrays with tunable singularity.
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